Improve me nt in air-pumps



D.'E. BANGS.

, AIR-PUMP, No.173,154. v relented Feb .8,18 76.

NJETERS. PIIDTO-UTHDGRAPNEFL WASHINGTON. D. C. v

NITED STATES:

PATENT OFFICE x p DAVID E. BANGS, OF MEDFORD, MASSACHUSETTS.

IMPROVEMENT IN AIR-PUMPS.

' Specification forming part of Letters Patent No. 173,154, dated February 8, 1876; application filed December 15, 1875.

To all whom it may concern:

Be it known that I, DAVID E. BANGS, of th town of Medford, county of Middlesex and State of Massachusetts, have invented certain Improveinen ts in Air-Pumps, of which the following is a specification:

This invention relates to certain improve ments in air-pumps; and consists of an upright cylinder having an annular space at the outer edge of its lower half, containing glycerine or other liquid, to serve as packing for the bell-shaped piston-head, the sides of which fit into the annular space. It being immersed in the liquid prevents'any communication bevided with suitable valves, by which air is allowed to pass inward when the motion of the piston is in one direction, and outward when the motion is in the opposite direction.

The valves opening outward are connected with pipes which are connected with a pipe that is common to both, so that when a reciprocating motion is imparted to the piston a constant and steady flow of air will be maintained. The advantages of this arrangement are, that a constant flow of air can be maintained by,

the use of only one cylinder, and that, owing to the small quantity of liquid employed, the liability of vaporarising therefrom to be carried off with the air is very much lessened,

and thereby delivering the air in a pure and dry state.

In the drawing, Figure 1 is a top view of the cylinder, showing the stuflEing-box c, inletvalve a, and the outlet-pipe 0. Fig.2 shows a vertical section of the cylinder, taken in the line of its center, A being the cylinder, B the piston, and O the annular space to hold the liquid packing. Fig. 3 is a sectional view of the inlet-valve.

By reference to the drawing, the operation of my invention will be readLy understood. Motion being imparted to the piston in a downward direction, the air in the lower part of the cylinder will be forced out through the pipe 6, the valve b opening outward and preventing its return. At the same time the inlet-valve a opens by the pressure of the atmosphere, and fills the upper .part of the cylinder with air, to be in turn forced through the pipe c on the upward movement of the piston,-the valve a operating the same as a on the downward movement.

I am aware that other devices have been used with which a pressure of air is produced by the weight of an=inverted bell resting in water, the same as the gasometer in common use; but

What I claim as new, and desire to secure by Letters Patent, is

- The combination of the covered cylinder A with piston B, with rod working through stuffin g-box c, and operating to produce a constant current of air, substantially as described.

DAVID E. BANGS.

Witnesses:

W. S. HILL, W. T. WYMAN. 

